Bar codes are constituted by a coded succession of specifically grouped bars having a determined height H and a determined width D, or spaces void of bars. Codes of this type are used for marking items such as postal objects, checks, banker's drafts or the like, which are subsequently to be handled, e.g. sorted, checked, stored, etc.
The marking of objects with bar codes is generally performed by means of bar code marking machines of a particular type. Now, it is advantageous -especially from an economic point of view- to generate bar codes by using certain capital letters of conventional standard typewriters. In this case only the vertical lines forming the letter are used while the remaining lines, i.e. the horizontal or curved lines are considered as flaws and are consequently eliminated.
However, the code bar detection devices and reading heads currently used up till now are not adapted to the use of capital letters for producing bar codes.
The present invention aims at overcoming this drawback by providing a novel code bar detection process.